Typically, solar panels may have a string of cells connected in series. As shown in FIG. 1, panel 100 has a string of cells 101ab-101nn connected in series. As illustrated, panel 100 is a 9×4 series of cells or slices. Two leads 102a,b deliver the series voltage of all the cells together. If one of the cells is defective, shaded, dirty, or otherwise degraded, it can reduce the output performance of the whole panel.
FIG. 2 shows a typical setup for a solar array system 201, in which a number of parallel strings of serial panels P11 to Pnn are used. If some of these panels are in a shaded area, as delineated by line 203a . . . n, the performance of the whole array 202ab-202nn may be undesirably affected. The strings are connected in parallel by lines 204, which may typically connect to an inverter.
FIG. 3 shows a solar array system 301 having panels 302a . . . n, with each panel having an attached management unit 304a-n. Each panel 302a . . . n and its associated management unit 304a-n are connected in parallel. Each of the management units 304a-n converts the voltage of the associated panel to high voltage for transmission on a bus. If a particular panel is shaded or if its performance is degraded by any other factors, this approach can help to limit the undesirable impact to the particular panel that is affected Degradation of the performance of the string, of which the affected panel is a part, can be reduced to some degree.
Improved efficiency of panels, both by themselves as well as in larger groups, is needed.